Effects of prenatal exposure to temephos on behavior and social interaction.

The neurodevelopment period is susceptible to alterations by genetic and environmental factors, such as the exposure to organophosphates (OP). The OP is neurotoxic and has been associated with neurological diseases pathophysiology. The OP temephos is widely used against Aedes aegypti in Brazil's public health programs. PURPOSE: To evaluate behavioral effects of prenatal exposition to temephos in Wistar rats. METHODS: First, we divided pregnant females into groups: those who received temephos diluted in distilled water by gavage between gestational days 6-13 and those who received only distilled water in the same period and volume. Then, we divided pups according to sex and exposure, and we made the behavioral tests on postnatal day 30. RESULTS: Prenatal exposure to temephos caused hyperactivity, stereotyped behavior, and social impairment in animals. CONCLUSION: These results are similar to the altered behavior presented in some neurobiological diseases models, like Attention Deficit Hyperactivity Disorder and Autism Spectrum Disorders, and this study may bring a red alert to the large use of temephos in Brazil, due to the damage caused by its exposure.

Alpha-lipoic acid attenuates acute neuroinflammation and long-term cognitive impairment after polymicrobial sepsis.

Sepsis is a complication of an infection which imbalance the normal regulation of several organ systems, including the central nervous system (CNS). Evidence points towards inflammation and oxidative stress as major steps associated with brain dysfunction in sepsis. Thus, we investigated the α-lipoic acid (ALA) effect as an important antioxidant compound on brain dysfunction in rats. Wistar rats were subjected to sepsis by cecal ligation and perforation (CLP) or sham (control) and treated orally with ALA (200 mg/kg after CLP) or vehicle. Animals were divided into sham + saline, sham + ALA, CLP + saline and CLP + ALA groups. Twelve, 24 h and 10 days after surgery, the hippocampus, prefrontal cortex and cortex were obtained and assayed for levels of TNF-α and IL-1ß, blood brain barrier (BBB) permeability, nitrite/nitrate concentration, myeloperoxidase (MPO) activity, thiobarbituric acid reactive species (TBARS) formation, protein carbonyls, superoxide dismutase (SOD) and catalase (CAT) activity and neurotrophins levels. Behavioral tasks were performed 10 days after surgery. ALA reduced BBB permeability and TNF-α levels in hippocampus in 24 h and IL-1ß levels and MPO activity in hippocampus and prefrontal cortex in 24 h. ALA reduced nitrite/nitrate concentration and lipid peroxidation in 24 h in all structures and protein carbonylation in 12 and 24 h in hippocampus and cortex. CAT activity increased in the hippocampus and cortex in all times. ALA enhanced NGF levels in hippocampus and cortex and prevented cognitive impairment. Our data demonstrates that ALA reduces the consequences of polymicrobial sepsis in rats by decreasing inflammatory and oxidative stress parameters in the brain.

Effects of ω-3 fatty acids on stereotypical behavior and social interactions in Wistar rats prenatally exposed to lipopolysaccarides.

OBJECTIVE: Supplementation with ω-3 polyunsaturated fatty acids (PUFAs) can positively contribute to neurologic development, modulating inflammatory responses, promoting homeostasis, and having a positive effect on animal behaviors associated with mental disorders. The aim of this study was to evaluate behavioral and biochemical effects of ω-3 fatty acid supplementation in an animal model for mental disorders by prenatal maternal exposure to lipopolysaccardies (LPS) from the maternal immune activation. METHODS: Twelve pregnant Wistar rats were used. Each rat received 100 µg/kg of LPS or saline solution on gestational day (GD) 9.5. The offspring remained with mothers until weaning and from postnatal day (PND) 30 were supplemented with ω-3 PUFA or saline solution by gavage at a dose of 0.8 g/kg orally for 21 d. On PND 52, the animals underwent behavioral tests; then, they were sacrificed, and the brain structures were dissected and analyzed by levels: neuron-specific enolase (NSE), brain-derived neurotrophic factor, and transforming growth factor (TGF)-ß. RESULT: Prenatal exposure to LPS significantly increased the episodes of stereotyped movements and decreased social interaction in the offspring (P = 0.009 and P = 0.001, respectively), after ω-3 PUFA supplementation these parameters reversed (P = 0.005 and P = 0.013, respectively). Significant changes also were identified in the biochemical analysis in NSE and TGF-ß in the brain structures; these conditions were reversed after ω-3 PUFA supplementation. CONCLUSION: Supplementation with ω-3 PUFA reversed animal behaviors that often are observed in autism and other mental disorders in rats prenatally exposed to LPS, and also exerted neuroprotective effects in marker levels of neuronal damage and expression of TGF-ß.